Optimizing Design and Performance of Underwater Acoustic Sensor Networks with 3D Topology

This study aims to optimize the design and performance of three-dimensional (3D) underwater acoustic sensor networks (UASNs). First, we develop an analytical model to quantify network performances in terms of the packet queueing delay and packet error probability for sensors in a 3D UASN. The model considers the retransmission delay due to packet transmission errors and packet collisions when calculating the packet queueing delay. The packet queueing delay depends on the choice of medium access control (MAC) protocol. We consider two different MAC protocols: slotted ALOHA and Request-to-Send and Clear-to-Send (RTS/CTS)-based MAC, which are the representative random access-based and handshake-based MAC protocols for UASNs, respectively. Based on the model, we further determine the smallest data sink density required to meet the desired packet error probability requirement for underwater sensor density, which can help network operators to design and build UASNs in a cost-effective way. To do this, we formulate a simple optimization problem that aims to minimize the data sink density while guaranteeing an upper bound for packet error probability. Using extensive numerical evaluations, network operation strategies are then presented to achieve the desired performance requirements in 3D UASNs.